Domina, 62, will be officially kicking off his campaign on Tuesday at the State Capitol in Lincoln. He joins at least four Republicans and one independent who are all already vying for the seat being vacated by Sen. Mike Johanns (R-Neb.), who is retiring. Candidate Larry Marvin is also running on the Democratic side, although the Lincoln Journal Star notes that "he is not likely to have the campaign resources that would allow him to compete."
In an interview with The Huffington Post on why he is entering the race, Domina said he was concerned that the way government is being run is hurting the country's security.
"If we gridlock and close the government, gridlock and can't pass a budget, gridlock and can't pay the bills, the problem is with the country losing respect in the international community, people paying attention to our ability to defend ourselves at home and our people being less safe. There is a direct connection between those consequences and the safety of the American people," he said.
Most recently, Domina has been receiving attention for representing Nebraska landowners who are trying to stop the controversial Keystone XL pipeline. He has helped them challenge the law that gave the governor the power to take away their property for the project.
The $7 billion pipeline, which would be built by TransCanada Corp., would connect the oil sands in western Canada to refineries in Texas. The Obama administration has delayed making a decision on whether to allow the project to go forward and has faced pressure to block it from environmental groups.
Last week, Secretary of State John Kerry said he would not be rushed into a making a decision.
"All [of my work on the pipeline has been] designed to protect Nebraska landowners from the company and its odd decisions to put a pipeline where it proposes to across Nebraska, instead of twinning the pipeline it has right now," said Domina. "The company has a pipeline all the way across the state, it got it with almost no fight, and it won't put this one in the same place. Instead it wants to run across that aquifer out there, which is foolish. And Nebraskans know it's foolish."
Domina said that beyond the Nebraska-based issues, however, he also more broadly opposes the pipeline and would like to see the Obama administration block it.
"The reason why that I'd like to see the president not approve it is that there are so many environmental concerns about a pipeline of that kind being operated by an irresponsible owner, who has treated people the way that this company has treated Nebraska. If I were the president, that would tip me over on this application by this company for this pipeline on this route," he said.
Still, Domina said the pipeline would be a secondary concern if he makes to the Senate. More importantly, he argued, the country needs to be "stabilized" and the country needs to "come to grips with the fact that we have to pay the bills, we have to keep the government open, we have to make intelligent decisions about the military so we don't face in the future funding problems with older military personnel."
Domina also said he supports raising the minimum wage to at least $10.10 an hour -- which has been a focus of Democrats and the White House -- and perhaps even higher.
"I think that there needs to be an economic inquiry made about that immediately after it's raised to $10, and the reason I say that is we've been stuck on trying to get to $10 for a long time," said Domina when asked about whether $10.10 is enough. "We need to get there first."
Nebraska is a solidly red state that Republican Mitt Romney handily won in the 2012 elections. Domina declined to call himself a progressive, saying instead, "I'd like to identify myself as reasonable and focused on what's good for the United States."
But in 2012, Democrats picked up a seat in the red plains states, when Heidi Heitkamp won in North Dakota. Domina said he believed he could take some lessons from her race and apply them to his own.
"I would take two or three lessons," he said. "Here's the first one. Be focused on what's good for the United States first, Nebraska second. Understand the facts, understand what the law is today. Evaluate what it ought to be and then make a reasoned judgment. Do not simply chase approval by groups or organizations."
Domina ran for governor in 1986 but lost the Democratic primary. There were rumors that he would possibly challenge Rep. Lee Terry (R-Neb.) -- whose main Democratic challenger dropped out last month -- but Domina said that although he was also urged to consider that race, he wanted to serve the entire state.
"I was asked to consider it by thoughtful people," Domina said, "and I considered it out of respect for them and reevaluated what was going on in my own head and decided I needed to stay focused with what I was willing to do because my spirit moved me in one direction and not the other."
"I live in Omaha now, but my roots are in rural Nebraska," he added. "I have spent so much of my life working for people in the 1st and 3rd Congressional Districts and helping them with their problems that I thought if I'm going to give a great big chunk of my life at this stage, I want to give it to all of them, and let them all have a chance to hire me or decide they don't want me to work for them."